A site where a man with far too much interest in beer gets to write about it.

Thursday, 5 May 2016

Home malting

As a brewer and microbiologist I have felt a certain smugness when contemplating the zombie apocalypse. Though civilisation may have collapsed around me, I'm sure with minimal equipment I could make my own beer. But once I'd thought it through a bit more a cold feeling of dread came upon me. Where will the malt come from? Making inferior fruit based beverages may be a simple task, but making booze from a starchy substrate is an altogether more involved process. There was only one thing for it, I would have to try home malting.

My Mk II mash tun seemed like an ideal candidate for a steeping and germination vessel. It's made of a home brew bucket with holes drilled in the bottom inside another one with a tap at the bottom.

Here's the inside:

I decided to start with an overnight steep.

Here it is in the morning:

Draining it for the first air rest:

Air rest until the afternoon then the second steep:

And then drained again at night:

After two steeps and air rests it was ready for germination:

Chitted grains:

See the tips of the rootlets poking out

The rootlets start growing very quickly:

day 3

day 4

day 5

day 6

It's important to keep mixing the contents of the germination vessel to stop the roots tangling and hot spots developing. For the laboratory scale malting at work we take the grains out and shake them in a bucket. I thought rolling the vessel around, like a drum malting, would be enough but it wasn't. Look at this bolted bastard:

I'd had a clump in the middle that hadn't mixed and the grains had got a lot hotter and grown a lot more. Fortunately most of them were like this:

I decided to include a withering stage, letting them partially dry on the floor.

That a few grains had bolted showed that the germination process needs tweaking a bit but nothing too major. My real problems started with the kilning. Keeping the malt on a tray meant I could only put a small amount at a time in the oven. I left the rest on the floor to wither more, but it was a long and involved process to get it all kilned, and even then the moisture content was still high at just over 8%. Initially I heated with the oven at a very low setting to remove as much water as possible before cranking up to over 100°C for the final kilning.

I did even worse with removing the rootlets and in the end admitted defeat. I tried shaking the grains in a colander but as well as the roots falling through the holes quite a few grains did too. I could only do a very small amount of grains at a time too, so rather than spend hours doing it I gave in and used the machine at work. Who'd have though that one of the first tasks of a post-apocalyptic society will be to build a deculming machine?

Tune in for the next episode to see if I'll be happily sipping a pint as the zombie hordes hammer at my door or if the brewing all went horribly wrong.

Yes, we often get sent an excess of barley for malting projects and it seems to me it's better to put it to good use than send it to landfill. I don't know where you could buy barley. A friendly maltings might help, and grain merchants like Robin Appel are worth a try.

Really interesting. Have you tried germination on the floor? The raking and turning of malt on the floor is supposed to prevent tangling of rootlets. I'm sure it does, but it probably does a bit more than that. It also confuses the geotropism of the grain as it grows and slows down the growth of rootlets.

This is the only go I've had a home malting. I'm really enjoying the beer so I might give it another go later in the year. Having malt covering the kitchen floor is not ideal though, so I'll stick with drum malting!

Don't bother with a debearder for a batch that small. You can use a paint mixer on an electric drill. Just put the grain in a bucket and mix it with the paint mixer, it will remove all the rootlets and turn them into a fine dust. To remove the dust from the malt sift it through a screen of some sort.